吉林大学学报(工学版) ›› 2022, Vol. 52 ›› Issue (2): 296-309.doi: 10.13229/j.cnki.jdxbgxb20211031

• 车辆工程·机械工程 • 上一篇    

基于卷积神经网络和双向长短期记忆的稳定抗噪声滚动轴承故障诊断

陈晓雷1,2,3(),孙永峰1,李策1,2,3,林冬梅1,2,3   

  1. 1.兰州理工大学 电气工程与信息工程学院,兰州 730050
    2.兰州理工大学 甘肃省工业过程先进控制重点实验室,兰州 730050
    3.兰州理工大学 电气与控制工程国家级实验教学示范中心,兰州 730050
  • 收稿日期:2021-10-09 出版日期:2022-02-01 发布日期:2022-02-17
  • 作者简介:陈晓雷(1979-),男,副教授,博士.研究方向:模式识别与智能系统.E-mail:chenxl703@lut.edu.cn
  • 基金资助:
    国家自然科学基金项目(61967012)

Stable anti⁃noise fault diagnosis of rolling bearing based on CNN⁃BiLSTM

Xiao⁃lei CHEN1,2,3(),Yong⁃feng SUN1,Ce LI1,2,3,Dong⁃mei LIN1,2,3   

  1. 1.College of Electrical and Information Engineering,Lanzhou University of Technology,Lanzhou 730050,China
    2.Key Laboratory of Gansu Advanced Control for Industrial Processes,Lanzhou University of Technology,Lanzhou ;730050
    3.National Demonstration Center for Experimental Electrical and Control Engineering Education,Lanzhou University of Technology,Lanzhou 730050,China
  • Received:2021-10-09 Online:2022-02-01 Published:2022-02-17

摘要:

针对滚动轴承在噪声环境条件下故障诊断模型准确率较低和性能不稳定的问题,本文提出了一种稳定抗噪声故障诊断神经网络(SAFDNN)模型。该模型采用原始振动数据信号作为输入,首先使用卷积神经网络(CNN)进行数据信号特征提取,然后利用双向长短期记忆(BiLSTM)充分提取数据信号的序列特征,接着添加注意力机制进行特征融合以自动关注每种数据信号的相关信息,提高模型的诊断性能,最后通过全连接层和Softmax层进行特征分类。实验结果表明,SAFDNN在添加不同信噪比大小的额外噪声条件下能够保持较高的故障识别准确率和较好的诊断效果稳定性。

关键词: 故障诊断, 稳定抗噪声, 滚动轴承, 神经网络, 特征提取, 注意力机制

Abstract:

Aiming at the problem of low accuracy and unstable performance of the fault diagnosis model of rolling bearing in noise environment conditions, This paper proposes a stable anti?noise fault diagnosis neural network SAFDNN model. The model uses the original vibration data signal as input. First, the CNN is used to extract the characteristics of the data signal, and then the BiLSTM is used to fully extract the sequence characteristics of the data signal, and then the attention mechanism is added for feature fusion and automatically pay attention to the relevant information of each data signal, improving the diagnostic performance of the model, and finally performing feature classification through the fully connected layer and Softmax layer. The experimental results show that SAFDNN can maintain a higher fault recognition accuracy and better stability of the diagnosis effect under the condition of adding additional noise with different signal?to?noise ratios.

Key words: fault diagnosis, stability anti?noise, rolling bearing, neural network, feature extraction, attention mechanism

中图分类号: 

  • TP277

图1

SAFDNN模型结构框架"

图2

10种故障原始信号可视化图"

表1

数据采集信息"

负载转速/(r·min-1每转采集的数据个数
0.746 kW(1 hp)1772406
1.492 kW(2 hp)1750411
2.238 kW(3 hp)1730416

表2

数据增强后CWRU数据集详细信息"

数据集位置BallInner RaceOuter RaceNormal
标签0123456789
直径(inch)0.0070.0140.0210.0070.0140.0210.0070.0140.0210

A

0.746 kW(1 hp)

训练集360360360360360360360360360360
验证集120120120120120120120120120120
测试集120120120120120120120120120120

B

1.492 kW(2 hp)

训练集360360360360360360360360360360
验证集120120120120120120120120120120
测试集120120120120120120120120120120

C

2.238 kW(3 hp)

训练集360360360360360360360360360360
验证集120120120120120120120120120120
测试集120120120120120120120120120120

图3

BiLSTM结构"

表3

SAFDNN网络结构参数"

编号网络层内核大小步长神经元数输出大小
1输入层???800×1
2卷积164×1832100×32
3池化12×123250×32
4卷积23×116450×64
5池化22×126425×64
6BiLSTM??3225×64
7注意力模块??100100×1
8全连接??3232×1
9Softmax??1010×1

图4

原始轴承球体故障信号和添加SNR=-4 dB信号可视化图(a) 原始信号 (b) 添加信号SNR=-4 dB"

表4

不同批量大小在不同SNR条件下测试实验结果"

batch_sizeSNR
-10-8-6-4-20246810
6476.57±1.4284.56±0.8991.37±0.9494.44±0.8796.22±0.4797.28±0.6498.23±0.4198.35±0.3198.59±0.5398.59±0.4198.75±0.38
12880.18±1.2485.95±1.6791.51±0.9194.83±0.5896.85±0.6698.04±0.2998.42±0.3298.42±0.2798.59±0.3398.71±0.5898.86±0.36
20080.36±1.2887.32±1.0491.78±0.7195.36±0.5697.28±0.4198.17±0.3598.75±0.2799.03±0.2199.03±0.2698.66±0.2699.22±0.29
25679.84±1.6386.88±1.9792.74±0.7995.81±0.7197.23±0.5397.95±0.4198.11±0.6198.33±0.6498.42±0.4598.65±0.3398.64±0.36

图5

数据集A、B、C分别添加SNR=-4 dB的条件下验证集准确率和损失值变化曲线"

图6

SNR=-4dB的条件下,不同数据集测试混淆矩阵"

图7

不同噪声条件下,不同模型在各个数据集上的测试结果"

表5

数据集A不同SNR条件下不同模型测试结果(%)的稳定性比较"

模型SNR
-10-8-6-4-20246810
SAFDNN81.89±1.3486.89±1.0893.28±0.8395.52±0.5397.65±0.3798.14±0.3698.55±0.2198.90±0.1999.14±0.2499.44±0.2299.75±0.15
CNN+BiLSTM80.35±1.5385.88±1.0892.74±0.6795.28±0.7296.67±0.5797.53±0.5198.43±0.4498.61±0.4398.83±0.3798.97±0.3199.29±0.20
WDCNN75.93±2.9285.75±1.5991.21±1.4394.92±0.9296.57±0.7297.43±0.7197.88±0.5898.01±0.4198.26±0.6198.64±0.3398.86±0.30
TICNN76.17±3.5782.08±3.1689.76±2.9893.82±1.7195.08±1.4296.75±1.2997.36±1.2297.61±0.8398.27±0.6398.65±0.5198.88±0.25
CNN+Attention68.66±1.9474.52±1.6079.27±1.8883.96±1.1187.57±0.9390.33±1.2892.82±0.6293.69±1.2895.08±0.5195.54±0.7396.47±0.54
AAnNet59.90±5.5367.64±4.4075.71±2.5181.49±2.9488.22±2.1595.44±1.7796.68±1.4397.39±0.9498.33±0.6998.73±0.7598.87±0.32

表6

数据集B不同SNR条件下不同模型测试结果(%)的稳定性比较"

模型SNR
-10-8-6-4-20246810
SAFDNN86.00±1.4391.94±0.7096.23±0.4998.71±0.2899.42±0.2799.82±0.0999.90±0.0999.91±0.0699.94±0.0699.93±0.0499.95±0.04
CNN+BiLSTM84.63±1.4290.97±1.0595.94±0.6698.71±0.4899.22±0.4199.64±0.3399.83±0.1299.86±0.1499.91±0.0699.92±0.1099.85±0.12
WDCNN75.75±3.2785.54±2.1191.92±1.0896.59±0.8198.33±0.4198.98±0.6699.64±0.2699.40±0.5699.83±0.1099.74±0.1899.87±0.11
TICNN80.28±3.4785.59±4.3491.39±3.5996.96±1.2599.14±0.3598.97±0.9199.80±0.1599.84±0.1199.50±0.6799.68±0.4199.88±0.10
CNN+Attention70.33±1.8478.05±2.5084.73±2.0190.19±1.0492.42±1.5595.36±0.9496.98±0.5097.50±0.3597.83±0.7998.49±0.2898.34±0.44
AAnNet63.41±4.7871.61±3.4680.91±2.8790.79±2.3395.83±1.2096.53±1.6897.04±0.9997.76±0.6798.34±0.5199.02±0.5199.21±0.42

表7

数据集C不同SNR条件下不同模型测试结果(%)的稳定性比较"

模型SNR
-10-8-6-4-20246810
SAFDNN87.27±1.0192.05±0.5596.58±0.4098.17±0.3699.38±0.2699.67±0.2099.67±0.1199.78±0.0799.89±0.0599.95±0.0499.93±0.07
CNN+BiLSTM85.95±1.2390.65±0.7896.43±0.4898.58±0.4399.35±0.3799.56±0.2899.65±0.1999.69±0.1499.77±0.0999.80±0.1499.89±0.07
WDCNN82.88±3.3188.33±2.2193.91±1.7096.03±1.0598.00±0.5398.60±0.8199.32±0.3299.33±0.2199.66±0.1699.71±0.1299.68±0.18
TICNN84.58±3.5789.22±1.7994.72±1.4397.00±1.1097.17±1.5399.10±0.4298.72±1.2499.25±0.5799.28±0.5999.56±0.2799.71±0.15
CNN+Attention74.91±2.2078.15±2.0583.00±1.8388.07±1.2691.99±1.4593.96±1.0095.60±0.5497.15±0.5697.80±0.3698.35±0.3598.27±0.25
AAnNet63.68±3.3169.61±2.1476.71±1.7782.45±1.5190.26±1.1195.74±0.8696.89±0.6897.63±0.5898.41±0.3398.88±0.2999.33±0.30

图8

SNR=-4dB的条件下,不同模型验证准确率和验证损失值变化曲线"

表8

消融实验不同模块使用情况"

编号ELU+BiLSTMAttentionData Enhancement
1×××
2××
3××
4××
5×
6×
7×
8

表9

不同噪声条件下消融实验测试结果(%)的稳定性比较"

编号SNR/dB
-10-8-6-4-20246810
134.67±6.4545.75±6.1747.93±5.6160.56±4.9164.37±4.5368.54±3.5973.41±3.1580.73±2.9587.85±2.5789.41±2.4393.37±1.86
268.47±3.4777.05±2.9783.47±2.7388.53±2.5393.10±1.9595.87±1.8297.34±1.5798.61±1.5298.59±1.3799.15±1.2999.35±1.21
345.59±5.1756.73±4.3158.14±4.0565.96±3.7572.16±3.4978.63±3.1582.51±2.5487.58±2.4792.36±1.9595.25±1.3797.31±1.35
467.37±2.3578.41±2.8785.35±2.4390.54±1.9694.07±1.6896.18±1.5297.39±1.3698.67±1.2398.73±1.1998.74±1.2598.80±1.13
572.28±2.0578.75±1.3885.98±1.2894.83±1.1595.69±1.6295.77±1.4897.51±1.0497.89±0.6698.44±0.4799.49±0.3999.29±0.40
684.63±1.4290.97±1.0595.94±0.6698.71±0.4899.22±0.4199.64±0.3399.83±0.1299.86±0.1499.91±0.0699.92±0.1099.85±0.12
771.59±2.1780.71±1.7785.04±1.5490.79±1.7594.36±1.3696.34±1.0997.60±0.9798.77±0.8199.07±0.5999.53±0.4699.45±0.42
886.00±1.4391.94±0.7096.23±0.4998.71±0.2899.42±0.2799.82±0.0999.90±0.0999.91±0.0699.94±0.0699.93±0.0499.95±0.04

表10

交叉训练、验证和测试数据集分布"

编号训练集验证集测试集
1ABC
2ACB
3BAC
4BCA
5CAB
6CBA

图9

不同负载条件下不同模型测试结果比较"

表11

不同负载条件下不同模型测试结果(%)的稳定性比较"

模型ABCACBBACBCACABCBA
SAFDNN98.28±0.9599.91±0.0599.39±0.5497.61±0.3391.43±2.5587.27±1.56
CNN+BiLSTM98.47±1.0899.93±0.0799.27±0.7497.37±0.5290.10±2.7081.24±1.49
WDCNN95.93±1.1498.75±1.0094.46±2.3996.41±0.8984.83±3.7378.26±2.33
TICNN93.19±3.2399.46±0.4593.45±1.5893.83±1.5482.38±3.1076.70±1.93
AAnNet72.99±2.1979.74±2.9690.78±1.7784.25±2.5866.59±4.0662.13±3.78

图10

SNR=-4 dB不同负载条件下不同模型测试结果比较"

表12

SNR=-4 dB时不同负载条件下不同模型测试结果(%)的稳定性比较"

模型ABCACBBACBCACABCBA
SAFDNN95.74±0.5397.22±0.5296.13±1.1292.18±0.9796.86±1.1693.05±0.68
CNN+BiLSTM95.13±0.7297.15±0.5996.18±0.7892.42±1.4596.94±0.8293.02±1.30
WDCNN92.58±1.4993.66±1.2093.14±2.0590.87±1.2092.06±1.9392.04±1.68
TICNN93.70±1.4294.15±2.6193.80±1.2990.37±1.1895.26±1.8190.58±2.20
AAnNet59.27±2.3562.81±2.0163.69±2.6164.58±1.9650.01±3.3156.21±3.23
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